in Java, Why is the delete function faster in the linked list than an array ?
In Java (and in general programming), the performance of delete operations in a linked list compared to an array can be attributed to the underlying data structures and how they manage memory.
Node Structure: A linked list consists of nodes, where each node contains data and a reference (or pointer) to the next node. To delete a node, you only need to adjust the pointers of the previous node to bypass the node to be deleted.
Time Complexity: The time complexity for deleting a node in a linked list is O(1) if you have a reference to the node to be deleted (or O(n) if you need to search for it). This is because you only need to change a couple of pointers.
No Shifting Required: When you delete a node, you do not need to shift any other nodes. The remaining nodes stay in place, and you simply update the pointers.
Contiguous Memory: An array is a collection of elements stored in contiguous memory locations. When you delete an element from an array, you need to maintain the order of the remaining elements.
Time Complexity: The time complexity for deleting an element from an array is O(n) in the worst case. This is because, after removing an element, all subsequent elements must be shifted one position to the left to fill the gap.
Memory Management: Arrays have a fixed size, and if you delete an element, you may also need to manage the size of the array, which can involve creating a new array and copying elements over if you want to maintain a dynamic size.
Thus, in scenarios where frequent deletions are required, linked lists are generally more efficient than arrays. However, it's important to note that linked lists have their own trade-offs, such as higher memory overhead due to storing pointers and potentially poorer cache performance compared to arrays.